Amalgamator for mixing dental fillings

ABSTRACT

An amalgamator for mixing dental fillings, having an electric motor with the armature shaft extending to both sides of the motor. A capsule holder is coupled to each of the armature shaft ends so that there are two movable holders for independently mixing two different dental fillings. The holders are operably connected with the electric motor to have strokes which are of different lengths and which substantially cancel each other to thereby minimize the vibration of the amalgamator. Also, automatic and manual switch means are provided for alternate running of the motor so that it can be operated at selectable lengths of time.

United States Patent Werner A. Paterson 3222 N. Main St., Racine, Wis. 53402 813,651

Apr. 4, 1969 June 8, 1971 Inventor Appl. No. Filed Patented AMALGAMATOR FOR MIXING DENTAL FlLLlNGS Primary Examiner- Donald G. Kelly Attorney-Arthur J. Hansmann ABSTRACT: An amalgamator for mixing dental fillings, having an electric motor with the armature shaft extending to both sides of the motor. A capsule holder is coupled to each of the armature shaft ends so that there are two movable holders for independently mixing two different dental fillings. The holders are operably connected with the electric motor to have strokes which are of different lengths and which substantially cancel each other to thereby minimize the vibration of the amalgamator. Also, automatic and manual switch means are provided for alternate running of the motor so that it can be operated at selectable lengths of time.

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AMALGAMATOR FOR MIXING DENTAL FILLINGS This invention relates to an amalgamator for mixing dental fillings, including the fillings for a person's front teeth and the fillings for a persons molars. This amalgamator is of the type commonly used by dentists in mixing the materials used in making fillings for a patients teeth. Thus the dentist obtains the necessary chemicals for the fillings and places them into capsules and holders on the amalgamator and operates the amalgamator to cause the materials to be mixed and thereby prepared for positioning on the patients teeth.

BACKGROUND OF THE INVENTION Amalgamators for use by dentists are commonly known. For instance, US. Pat. No. 2,201,428 shows an amalgamator with an electric motor and a holder for receiving the capsule with the materials to be mixed for providing the filling compound. The operation of the motor causes the holder to be vibrated and thus the filling materials are mixed in the capsule.

There are several problems with these prior art amalgamators. One is that the vibration of the single holder is such that the entire amalgamator commonly is bolted to a fixed position so that it will not move. Also, the vibrations are such that they can easily disturb other items sitting on a common table top with the amalgamator, and the amalgamator is noisy. Another problem is that the length of stroke of the holder is fixed and with only one holder only one length of stroke is possible, though this is not desirable for different conditions and different compounds desired for the filling material. Still another shortcoming ofthe prior art amalgamators is that the length of time which they operate is not readily and easily controlled.

The purposes of the present invention are to overcome the problems mentioned in connection with the prior art amal'g'amators, and it is a general object of this invention to provide an improved amalgamator. Therefore the present invention provides an amalgamator which minimizes vibration of the entire machine, and which provides the desired length of stroke of the capsule containing the ingredients to be mixed for the filling. Still further, these problems are overcome through the means of an efficient and easily manufactured and operated machine, and one which gives the advantages described in this document.

More specifically, the amalgamator of this invention provides two capsule holders which have their strokes in opposite directions so that they substantially cancel each other and thereby eliminate vibration of the machine. Further, the stroke of one holder is greater than the stroke of the other holder, and this permits the desired conditions for mixing different ingredients for different fillings. That is, in fillings for front teeth, the materials include silica and a liquid hardener, and for these materials a maximum stroke is wanted in order to get the best mix for the fillings for the front teeth. However, in mixing the ingredients for the fillings for the molars, and these ingredients are commonly mercury and silver, a shorter stroke is desired because these ingredients will heat too much if the longer stroke used for the silica is also used for the molar filling ingredients. For these reasons, the amalgamator of the present invention is provided with two holders having two different strokes or displacements for achieving the mix of the ingredients mentioned. Still further, this desirable result of different mixing action for the different ingredients is accomplished in the present invention through the means of only a single-speed motor so that no rheostat or like element is required for controlling the speed of the motor. Thus the single speed motor can be operated at its common running speed of from 3200 to 3500 r.p.m. for the best speed for the mixing mentioned. At that optimum speed, the displacement or stroke of the small stroke holder may be five-eighths of an inch while the displacement of the large stroke holder may he fifteen-sixteenths of an inch. The present amalgamator therefore readily and easily provides the optimum mixing action for the two different filling compounds, though only one machine is required and the two different mixes are provided. Further, the capsules commonly contain the ingredients mentioned and they also contain a pestle. It is common practice to operate the amalgamator for a given time of say 15 seconds, after which the pestle is removed from the capsule and the amalgamator is operated for a short period to have the ingredients in the capsule removed from the inner walls of the capsule. The present invention provides for this two-stage operation, and it does so by having an electric timer switch available for setting the desired amount of time during which the pestle is in the capsule. Then, when the pestle is removed, a manually operable switch is available to run the motor for a very short interval of time of perhaps only a second or 2. Such short time cannot be accurately controlled by any commonly available automatic electric timer, so the manual switch becomes significant and important. It should also be understood that once the pestle is removed from the capsule the ingredients may start to harden, though the vibration or shaking is still going on, so this must be closely controlled in time and therefore the manual switch provides for operation for the collection of the ingredients in the capsule but does not permit further hardening or amalgamation of those ingredients.

SUMMARY OF THE INVENTION The invention is the provision of an amalgamator having two holders which operate simultaneously and in a manner which causes one holder to cancel the vibrations of the other holder and thereby reduce the vibrations of the entire amalgamator. Also, the two holders have different lengths of strokes or displacements so that different characteristics are obtainable in the actions of the two holders relative to each other. This permits the mixing of different ingredients for the front filling and for the molar filling in a person's teeth. Still further, the amalgamator is provided with electric elements and electric controls which permit operation of the electric motor for desired lengths oftime so that optimum mixing conditions are readily obtainable.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an end elevational view of an amalgamator of this invention.

FIG. 2 is a side elevational view of one holder shown in FIG. 1.

FIG. 3 is a view of a fragment of the amalgamator shown in FIG. 1.

FIG. 4 is an end view of FIG. 3.

FIG. 5 is a diagrammatic view of the electric system employed in the amalgamator in FIG. 1.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT The amalgamator includes a base 10 supportable on feet 11. A platform 12 is affixed to the base 10 by means of the cushion mountings 13 and bolts 14. A conventional type of electric motor 16 is also mounted on the platform 12, and it is secured by the bolts 17 which anchor the motor support arms 18. Thus the arms 18 hold the conventional motor field having the laminations l9, and the latter carries the usual armature support members 21 extending along both sides of the motor 16. Thus the usual armature 22 is rotatably supported in the supports 21 by having the armature present its two armature extending shaft ends 23 through the motor supports 21. Finally, the usual motor winding section 24 is also shown and extends adjacent the field laminations 19 in the well-known manner. Therefore, the motor 16 is ofa common type and one which is well known to anyone skilled in the art, and it is a single-speed-type motor.

Of course the armature shuft has its extending ends 23 rotatably mounted and extending into couplers 26 and 27 which are affixed to the shaft ends 23 by means of setscrews 28.

The coupler 26 has a shaft 29 extending into a holder generally designated 31. The holder 31 includes a clamp member 32 which carries a double-row ball bearing 33 surrounding the coupler shaft 29. A screw 34 retains the holder 31 relative to the coupler 26. A tension coil spring 36 has its lower end 37 anchored on the platform 12, and the spring upper end 33 hooks onto the holder 31 by means of the screw 39. FIG. 2 shows the spring end 38 extending around the screw 39, and P10. 2 also shows that the holder clamp 32 is split or separated at the location designated 41. Thus the holder 32 can be disassembled relative to the ball bearing 33, and the spring 36 can also be removed from the holder 31.

The upper end of the holder 31 includes two spacedapart spring arms 42 which are secured to the member 32 by means of the four screws 43. The arms 42 are of spring material, and this permits the arms to move toward and away from each other so that they can receive and release a capsule 44 which contains the filling ingredients previously mentioned.

An important feature is that there are two holders 31, and they are substantially identical, but it should be noted that the connecting couplers 26 and 27 are different. That is, the couplers have holes 46 and 47, respectively, and these holes are at selective angles relative to the axes of the couplers and which axes extend along the coupler shafts 29. The hole 46 in the coupler 26 is at a greater angle than that of the hole 47 in the coupler 27. The respective angles may be l and 7, and FIG. 4 indicates the somewhat different locations between these two holes.

With the different angles of holes 46 and 47, the holder 31 on the left in FIG. 1 will be caused to vibrate to a greater distance or stroke than that ofthe holder on the right in FIG. 1. Therefore, the holder on the left would have the mercury and silver ingredients for filling molars, since these ingredients require the greater stroke for optimum mixing conditions.

It will also be understood that the two holders 31 move toward and away from each other at the same time, so the overall vibration of the amalgamator is minimized. Thus operation of the motor for rotation of the armature 22 and the armature shaft ends 23 will cause identical rotation of the couplers 26 and 27. Since the couplers are at an angle relative to the axis of the armature shaft 23, the holders 31 are caused to move in a manner which induces an elongated orbital action in the capsules 44 and 45. Of course the tension coil springs 36 keep the capsules 44 and 45 in the uppermost position, as shown in FIG. 1, but they still permit the vibration or mixing action described. To further minimize vibration and to produce an efficient machine, the machine elements described are arranged so that the axis of the armature shaft 23 and the axes of the couplers 26 and 27 intersect substantially on the center plane of the ball bearing 23. That is, in the double-row bearing shown, the intersection would be between the two rows and along the axis of the coupler shaft 29.

FIG. shows a schematic wiring diagram which includes the electric motor 16 and the electric lines indicating the power lines 50 and 48. The view also shows a timer motor 49 which is an automatically operative electric motor incorporated in an electric timer 51. Through an electric connection 52, the power line 48 is connected to the timer motor 49 and to the timer motor automatic switch 53. Also, the power line 50 is connected to the timer and its switch 53. Therefore, the timer motor 49 is of a conventional type such that one can set the timer so that the switch 53 will close and the motor 49 will run until it is out of time and the switch 53 will automatically open. thereby stopping the flow of power to the drive motor 16. FIG. 5 further shows a manual electric switch 54 which is in bypass connection with the automatic timer 31. Thus a connecting line 56 extends from the power line 49 to the manual switch 54. Another line 57 extends from the manual switch to the line 53 which connects both the timer and the manual switch to the drive motor. it will therefore be seen that when the automatic switch 53 is open, closing the manual switch 54 will complete the circuit to the motor 16 and through the connections 56, 57, and 58 and across the power lines 48 and 50. In this manner, the dentist can set the timer for say a 1-minute mix ofthe respective ingredients in the capsules 44 and 45 and with the pestles in the capsules. When the pestles are to be removed but further shaking is required, then the automatic timer is stopped and the manual switch 54 is depressed for only 1 or 2 seconds, as required, for the precise control of the additional mixing required.

What 1 claim is:

1. In an amalgamator for use in mixing dental fillings, a base member, an electric motor mounted on said base member and including an armature and a shaft extending axially of said armature, capsule holder means movably anchored relative to said base member, coupler means interconnected between said armature shaft and said capsule holder means and arranged to rotate about an axis and in response to the rotation of said armature shaft, the axis of rotation of said coupler means being disposed at an angle to the axis of rotation of said armature shaft to effect back and forth motion of said capsule holder means upon rotation of said armature shaft, the improvement comprising said armature shaft having an extending end on each side of said armature, said capsule holder means including a holder for each of said armature shaft ends, said coupler means including a coupler interconnected between each of said holder means and each of said armature shaft ends, each of said couplers having an axis of rotation disposed at an angle relative to said axis of rotation of said armature shaft and with said angles being of different degrees of angularity relative to the axis of said armature shaft whereby said holders move with different amounts of back and forth motion to have different lengths of strokes relative to each other for different amalgamating actions of said holders.

2. The subject matter of claim 1, wherein said angles of said axes of rotation of couplers are oppositely inclined for producing opposite motion between said holders to have said holders simultaneously move toward and away from each other for minimizing the vibrations in said amalgamator as produced by the back and forth motion of said holder means.

3. The subject matter ofclaim 2, wherein said motor is a single speed motor useful in achieving the different amalgamating actions without the need of either variable motor speeds or speed converter means between said motor and said holders.

4. The subject matter of claim 1, including an automatic electric timer switch electrically connected to said motor for controlling the flow of current to said motor, a manual electric switch electrically connected to said motor and in bypass connection relative to said automatic timer switch for energizing said motor for a selected length of time when said automatic timer switch is open. 

1. In an amalgamator for use in mixing dental fillings, a base member, an electric motor mounted on said base member and including an armature and a shaft extending axially of said armature, capsule holder means movably anchored relative to said base member, coupler means interconnected between said armature shaft and said capsule holder means and arranged to rotate about an axis and in response to the rotation of said armature shaft, the axis of rotation of said coupler means being disposed at an angle to the axis of rotation of said armature shaft to effect back and forth motion of said capsule holder means upon rotation of said armature shaft, the improvement comprising said armature shaft having an extending end on each side of said armature, said capsule holder means including a holder for each of said armature shaft ends, said coupler means including a coupler interconnected between each of said holder means and each of said armature shaft ends, each of said couplers having an axis of rotation disposed at an angle relative to said axis of rotation of said armature shaft and with said angles being of different degrees of angularity relative to the axis of said armature shaft whereby said holders move with different amounts of back and forth motion to have different lengths of strokes relative to each other for different amalgamating actions of said holders.
 2. The subject matter of claim 1, wherein said angles of said axes of rotation of couplers are oppositely inclined for producing opposite motion between said holders to have said holders simultaneously move toward and away from each other for minimizing the vibrations in said amalgamator as produced by the back and forth motion of said holder means.
 3. The subject matter of claim 2, wherein said motor is a single speed motor useful in achieving the different amalgamating actions without the need of either variable motor speeds or speed converter means between said motor and said holders.
 4. The subject matter of claim 1, including an automatic electric timer switch electrically connected to said motor for controllIng the flow of current to said motor, a manual electric switch electrically connected to said motor and in bypass connection relative to said automatic timer switch for energizing said motor for a selected length of time when said automatic timer switch is open. 